Now got the car running nice and smooth. Found a few things:
- the egr vent solenoid valve was no good. I had a replacement from a harvest at a junkyard a few years ago, so quickly fixed that
- the throttle cable rubber had lost its anchor, and not staying put on the steel bracket when the throttle was pulled
- the crankshaft position sensor wires were incorrect. I have no connector on the 3 wires coming from the wire harness, so have to put each wire in the cpk by hand. I had put them in to match up the wire colors coming from the cpk, but that was not correct. The manual shows the green and blue wires on the outside, but doesn't show a 3rd red wire. Once I put the wires in this way, with the red in the middle, engine power returned like normal, and once I adjusted the idle screw, everything was good.